An organic light emitting device is a device in which a thin film including a fluorescent organic compound or a phosphorescent organic compound is sandwiched between an anode and a cathode. Further, electrons and holes are injected from the respective electrodes to generate exciton of the fluorescent compound or the phosphorescent compound, whereby the organic light emitting device emits light when the exciton return to a ground.
Recent progress of an organic light emitting device is remarkable, and the characteristics of the device enable a light emitting device with a high luminance at a low applied voltage, a variety of emission wavelengths, high-speed responsiveness, thin and light weight. From this fact, it is suggested that the device have potential to find use in a wide variety of applications.
However, the present situation calls for optical output with even higher luminance or higher conversion efficiency. In addition, many problems still remain to be solved regarding durability against the change over time due to long-term use, deterioration caused by atmospheric gas containing oxygen, moisture, or the like.
Further, when considering application to a full color display or similar device, the present art is still insufficient against problems relating to the needs for light emission of blue, green, and red with a high color purity.
The use of a benzofluoranthene compound as a component for an organic light emitting device has been proposed as a method of solving the above-mentioned problems. For example, in each of Japanese Patent Application Laid-Open No. 10-189247, Japanese Patent Application Laid-Open No. 2002-8867, and Chem. Master. 2003, 15, 4854-4862, a benzofluoranthene compound is used as a component for an organic light emitting device.